The majority of adolescents in need of mental health care do not receive any services. Although a large body of literature has identified numerous individual-level factors associated with adolescent mental health service use, there is a paucity of information concerning the role of socio-ecological or contextual factors that affect the use of mental health care among this population. This study addresses this gap in the literature by examining the associations among contextual factors in three domains (community sociodemographics, healthcare infrastructure, and government policies) and adolescents' use of counseling services in various settings. The specific aims of this study are to: (1) examine the community characteristics and policy environments that are associated with adolescents' use of counseling services in clinical settings; (2) examine the community characteristics and policy environments that are associated with adolescents' use of counseling services in their schools; and (3) determine the patterns of counseling service use across communities before and after accounting for individual characteristics. This study will use data from Wave I and Wave II of the National Longitudinal Study of Adolescent Health (Add Health) database. Add Health is a nationally representative school-based sample of adolescents in grades 7-12 that contains an already linked rich contextual database, enabling the derivation of study variables that will measure community-level characteristics from 1990 Census data, health care infrastructure variables from the 1995 Area Resource File, county-level policy variables from the 1994 U.S.A. Counties database, and state-level policy variables from the 1994 School Health Policies and Programs Study database and the 1993 State Government Finances database. The primary methods of analysis will include multilevel modeling and generalized estimating equations. All regression models will account for individual-level predisposing, enabling, and need-related characteristics to determine the associations between these contextual-level variables and use of counseling services net of individual differences. This study is relevant to public health because the findings will provide policy makers with information about how patterns of counseling service use vary across communities, and about which contextual factors are most associated with service use in clinical and school settings. Furthermore, this study will ascertain the extent to which supraindividual factors may be points of intervention "upstream" over and above individual-level factors. [unreadable] [unreadable] [unreadable]